Yvan Muller posted the fastest time in first free practice for the World Touring Car Championship’s maiden visit to the United States, but was only just ahead of Tom Chilton at Sonoma.

Alain Menu set the early pace before being knocked off top spot by Chevrolet teammate Muller, who recorded a best lap of 1m46.398. Chilton, continuing a good day for his family after younger brother Max won in GP2 in Singapore earlier, found the pace in his Team Aon Ford Focus to go second fastest – just 0.053 seconds off Muller.

Menu ended up third with Gabriele Tarquini fourth in his SEAT, six tenths off the pace. The BMWs of Norbert Michelisz and Mehdi Bennani were next ahead of Chilton’s teammate James Nash, with Franz Engstler eighth. Rob Huff was only ninth in his Chevrolet, nine tenths away from Muller.

Aleksei Dudukalo completed the top ten in the second Lukoil SEAT, with Pepe Oriola 11th, Stefano D‘Aste 12th, Darryl O’Young 13th, Tom Boardman 14th and Fernando Monje 15th.

After recording the fastest time of Friday’s test session, Alex MacDowall was down in 16th in his bamboo engineering Chevrolet. The Cumbrian brought out the red flags when he found the gravel, but still managed to return to the pits under his own steam. Tiago Monteiro was a lowly 17th, while ROAL Motorsport were off the pace with Alberto Cerqui and Tom Coronel in 18th and 19th. Robb Holland only got out towards the end of the session in his bamboo Chevrolet after waiting for a helmet but still clocked a faster time than Charles Ng.

Second practice is at 19:30 BST.